Main contention: "ACD [anthropogenic climate disruption] is progressing dramatically and abruptly... That there will be a massive die-off of humans seems inevitable, and the extinction of our species is very much a possibility."
Harvey, Irma, California wildfires, shrinking arctic ice, death of the Great Barrier Reef, Miami summer flooding, disappearing permafrost, etc. Things are already getting serious, and we're taking nowhere near the appropriate action.